Vitreous fluorophotometry (VFP) is a clinical procedure for measuring the spatial distribution of fluorescence along the optical axis in a human subject's vitreous following administration of a fluorescent dye. In this project the clinical instrument is a Fluorotron Master manufactured by Coherent, Palo Alto, CA, and the dye is fluorescein sodium given by intravenous injection. The purpose of the project is to improve the protocols for conducting the measurements, processing the output from the instrument, and analyzing the results from the population of normal subjects and patients. One disease for which VFP may be useful is diabetes and the associated pathology, diabetic retinopathy. Additional goals for this project are to evaluate VFP for use in 1) screening for early detection, and 2) monitoring for treatment efficacy in diabetes and other pathological conditions.